subversion/subversion-1.10.2-CVE-2018-11782.patch

https://bugzilla.redhat.com/show_bug.cgi?id=17330884

https://subversion.apache.org/security/CVE-2018-11782-advisory.txt

Fixes for CVE-2018-11782, svnserve get-deleted-rev assertion failure.

The svn protocol prototype for get-deleted-rev does not allow for a reply of
SVN_INVALID_REVNUM directly. A query having such an answer previously caused
the server to raise an assertion failure which could crash the whole process
or a thread or child process of it, depending on the build configuration of
the server.

To work around the problem without changing the protocol, we re-purpose the
obsolete error code 'SVN_ERR_ENTRY_MISSING_REVISION' to communicate this
'not deleted' reply to the client.

  - With a new client against a new server, such queries are now handled
    correctly.

  - With an old client against a new server, the client will report a more
    informative error message, and the server will not crash.

  - With a new client against an old server, the behaviour is the same as
    with an old client against an old server.

In addition, this fixes a similar problem whereby any regular error response
to a 'get-deleted-rev' query resulted in the server closing the connection,
process and/or thread (again depending on the build configuration). Now such
errors are correctly passed back to the client.

* subversion/libsvn_ra_svn/client.c
  (ra_svn_get_deleted_rev): Detect error SVN_ERR_ENTRY_MISSING_REVISION
    and convert it to a response of SVN_INVALID_REVNUM.

* subversion/svnserve/serve.c
  (get_deleted_rev): Respond with error SVN_ERR_ENTRY_MISSING_REVISION
    instead of an assertion failure if the answer is SVN_INVALID_REVNUM.
    If svn_repos_deleted_rev() returns an error, pass that error back to
    the client.

* subversion/tests/libsvn_ra/ra-test.c
  (commit_two_changes): New.
  (test_get_deleted_rev_no_delete,
   test_get_deleted_rev_errors): New tests.
  (test_funcs): Run them.
--This line, and those below, will be ignored--

Index: subversion/libsvn_ra_svn/client.c
===================================================================
--- subversion-1.10.2/subversion/libsvn_ra_svn/client.c.cve11782
+++ subversion-1.10.2/subversion/libsvn_ra_svn/client.c
@@ -3105,6 +3105,7 @@
 {
   svn_ra_svn__session_baton_t *sess_baton = session->priv;
   svn_ra_svn_conn_t *conn = sess_baton->conn;
+  svn_error_t *err;
 
   path = reparent_path(session, path, pool);
 
@@ -3116,8 +3117,20 @@
   SVN_ERR(handle_unsupported_cmd(handle_auth_request(sess_baton, pool),
                                  N_("'get-deleted-rev' not implemented")));
 
-  return svn_error_trace(svn_ra_svn__read_cmd_response(conn, pool, "r",
-                                                       revision_deleted));
+  err = svn_error_trace(svn_ra_svn__read_cmd_response(conn, pool, "r",
+                                                      revision_deleted));
+  /* The protocol does not allow for a reply of SVN_INVALID_REVNUM directly.
+     Instead, a new enough server returns SVN_ERR_ENTRY_MISSING_REVISION to
+     indicate the answer to the query is SVN_INVALID_REVNUM. (An older server
+     closes the connection and returns SVN_ERR_RA_SVN_CONNECTION_CLOSED.) */
+  if (err && err->apr_err == SVN_ERR_ENTRY_MISSING_REVISION)
+    {
+      *revision_deleted = SVN_INVALID_REVNUM;
+      svn_error_clear(err);
+    }
+  else
+    SVN_ERR(err);
+  return SVN_NO_ERROR;
 }
 
 static svn_error_t *
--- subversion-1.10.2/subversion/svnserve/serve.c.cve11782
+++ subversion-1.10.2/subversion/svnserve/serve.c
@@ -3505,8 +3505,21 @@
                                svn_relpath_canonicalize(path, pool), pool);
   SVN_ERR(log_command(b, conn, pool, "get-deleted-rev"));
   SVN_ERR(trivial_auth_request(conn, pool, b));
-  SVN_ERR(svn_repos_deleted_rev(b->repository->fs, full_path, peg_revision,
-                                end_revision, &revision_deleted, pool));
+  SVN_CMD_ERR(svn_repos_deleted_rev(b->repository->fs, full_path, peg_revision,
+                                    end_revision, &revision_deleted, pool));
+
+  /* The protocol does not allow for a reply of SVN_INVALID_REVNUM directly.
+     Instead, return SVN_ERR_ENTRY_MISSING_REVISION. A new enough client
+     knows that this means the answer to the query is SVN_INVALID_REVNUM.
+     (An older client reports this as an error.) */
+  if (revision_deleted == SVN_INVALID_REVNUM)
+    SVN_CMD_ERR(svn_error_createf(SVN_ERR_ENTRY_MISSING_REVISION, NULL,
+                                  "svn protocol command 'get-deleted-rev': "
+                                  "path '%s' was not deleted in r%ld-%ld; "
+                                  "NOTE: newer clients handle this case "
+                                  "and do not report it as an error",
+                                  full_path, peg_revision, end_revision));
+
   SVN_ERR(svn_ra_svn__write_cmd_response(conn, pool, "r", revision_deleted));
   return SVN_NO_ERROR;
 }
--- subversion-1.10.2/subversion/tests/libsvn_ra/ra-test.c.cve11782
+++ subversion-1.10.2/subversion/tests/libsvn_ra/ra-test.c
@@ -94,6 +94,41 @@
   return SVN_NO_ERROR;
 }
 
+/* Commit two revisions: add 'B', then delete 'A' */
+static svn_error_t *
+commit_two_changes(svn_ra_session_t *session,
+                   apr_pool_t *pool)
+{
+  apr_hash_t *revprop_table = apr_hash_make(pool);
+  const svn_delta_editor_t *editor;
+  void *edit_baton;
+  void *root_baton, *dir_baton;
+
+  /* mkdir B */
+  SVN_ERR(svn_ra_get_commit_editor3(session, &editor, &edit_baton,
+                                    revprop_table,
+                                    NULL, NULL, NULL, TRUE, pool));
+  SVN_ERR(editor->open_root(edit_baton, SVN_INVALID_REVNUM,
+                            pool, &root_baton));
+  SVN_ERR(editor->add_directory("B", root_baton, NULL, SVN_INVALID_REVNUM,
+                               pool, &dir_baton));
+  SVN_ERR(editor->close_directory(dir_baton, pool));
+  SVN_ERR(editor->close_directory(root_baton, pool));
+  SVN_ERR(editor->close_edit(edit_baton, pool));
+
+  /* delete A */
+  SVN_ERR(svn_ra_get_commit_editor3(session, &editor, &edit_baton,
+                                    revprop_table,
+                                    NULL, NULL, NULL, TRUE, pool));
+  SVN_ERR(editor->open_root(edit_baton, SVN_INVALID_REVNUM,
+                            pool, &root_baton));
+  SVN_ERR(editor->delete_entry("A", SVN_INVALID_REVNUM, root_baton, pool));
+  SVN_ERR(editor->close_directory(root_baton, pool));
+  SVN_ERR(editor->close_edit(edit_baton, pool));
+
+  return SVN_NO_ERROR;
+}
+
 static svn_error_t *
 commit_tree(svn_ra_session_t *session,
             apr_pool_t *pool)
@@ -1784,6 +1819,56 @@
   return SVN_NO_ERROR;
 }
 
+/* Cases of 'get-deleted-rev' that should return SVN_INVALID_REVNUM. */
+static svn_error_t *
+test_get_deleted_rev_no_delete(const svn_test_opts_t *opts,
+                               apr_pool_t *pool)
+{
+  svn_ra_session_t *ra_session;
+  svn_revnum_t revision_deleted;
+
+  SVN_ERR(make_and_open_repos(&ra_session,
+                              "test-repo-get-deleted-rev-no-delete", opts,
+                              pool));
+  SVN_ERR(commit_changes(ra_session, pool));
+  SVN_ERR(commit_two_changes(ra_session, pool));
+
+  /* expect 'no deletion' in the range up to r2, when it is deleted in r3 */
+  /* This was failing over RA-SVN where the 'get-deleted-rev' wire command's
+     prototype cannot directly represent that result. A new enough client and
+     server collaborate on a work-around implemented using an error code. */
+  SVN_ERR(svn_ra_get_deleted_rev(ra_session, "A", 1, 2,
+                                 &revision_deleted, pool));
+  SVN_TEST_INT_ASSERT(revision_deleted, SVN_INVALID_REVNUM);
+
+  /* this connection should still be open: a simple case should still work */
+  SVN_ERR(svn_ra_get_deleted_rev(ra_session, "A", 1, 3,
+                                 &revision_deleted, pool));
+  SVN_TEST_INT_ASSERT(revision_deleted, 3);
+
+  return SVN_NO_ERROR;
+}
+
+/* Cases of 'get-deleted-rev' that should return an error. */
+static svn_error_t *
+test_get_deleted_rev_errors(const svn_test_opts_t *opts,
+                               apr_pool_t *pool)
+{
+  svn_ra_session_t *ra_session;
+  svn_revnum_t revision_deleted;
+
+  SVN_ERR(make_and_open_repos(&ra_session,
+                              "test-repo-get-deleted-rev-errors", opts, pool));
+  SVN_ERR(commit_changes(ra_session, pool));
+
+  /* expect an error when searching up to r3, when repository head is r1 */
+  SVN_TEST_ASSERT_ERROR(svn_ra_get_deleted_rev(ra_session, "A", 1, 3,
+                                               &revision_deleted, pool),
+                        SVN_ERR_FS_NO_SUCH_REVISION);
+
+  return SVN_NO_ERROR;
+}
+
 
 /* The test table.  */
 
@@ -1820,6 +1905,10 @@
                        "check how last change applies to empty commit"),
     SVN_TEST_OPTS_PASS(commit_locked_file,
                        "check commit editor for a locked file"),
+    SVN_TEST_OPTS_PASS(test_get_deleted_rev_no_delete,
+                       "test get-deleted-rev no delete"),
+    SVN_TEST_OPTS_PASS(test_get_deleted_rev_errors,
+                       "test get-deleted-rev errors"),
     SVN_TEST_NULL
   };